AMIKUQ: The Giant Octopus in Prince William Sound & Cook Inlet.
The project, Survey of octopus in the Intertidal, was started in 1995 in response to interest from native villagers in the Exxon Valdez oil spill impacted area. The residents of Tatitlek and Chenega Bay, in Prince William Sound, eat octopuses as part of their subsistence lifestyle; and had reported that octopuses became scarce in the years following the 1989 oil spill.
Our first year of field work was to establish the feasibility of working with octopus in Prince William Sound. Foot (intertidal) and SCUBA (shallow subtidal) searches were used to identify suitable study sites, and to estimate octopus densities and characterize octopus habitat in intertidal and nearshore waters. We found that it was feasible to survey octopus in the Sound with these techniques, although densities appear lower than in surveys done in British Columbia by Brian Hartwick in the 70's and early 80's.
In 1996, our second year of field work, we investigated octopus habitat use, movements, site-to-site variation in density, and diet. We tagged individuals with sonic-tracking devices, followed their movements with telemetry equipment, and monitored the occupancy of intertidal and subtidal dens. We also examined the Giant octopus's diet based on prey remains found in feeding litter, and documented prey availability in intertidal habitats.
Intertidal and subtidal searches provided the most data on the
characteristics of octopus habitats. SCUBA surveys proved that
octopuses were more abundant on shallow dives (to -5 m) than on deep dives.
In the intertidal octopuses were predominantly found on soft substrates (mud,
sand or gravel) rather than hard (bedrock, rock outcrops, and large
cobble fields); and where boulders were present rather than absent. In
the intertidal, octopus numbers increased with the percent cover of
broad-leafed kelps (e.g. Laminaria sp., Alaria sp.) in areas
adjacent to the areas surveyed. On dives, no association was found
with kelp cover. For a more detailed summary of those results, go to:
AMIKUQ: The Giant Octopus in Prince William Sound & Cook Inlet.
Since 1997, this research is aimed at a complete understanding of the ecology of the Giant Octopus, beginning with questions about habitat selection and regulation of local density. Answering these questions ultimately will lead to an understanding of what regulates octopus populations. This work (see publications) has been supported because of its relevance to questions of management and because of scientific interest in the life history of octopuses; as well as for contributions to marine research technology (see Shadow). Current research focuses on factors that play a role in the habitat selection of the Giant Pacific Octopus in Prince William Sound and Kachemak Bay, Alaska.
The Giant Octopus is an important component of coastal ecosystems from the Pacific Northwest to Japan, both as predator and prey of economically important species (e.g. as predator on crabs, clams, shrimp; as prey of halibut, cod, dogfish shark and pollock). Commercial interest in this species is growing as increasing demand and declining supply overseas may provide a market incentive to develop an Alaska fishery. Studies of the ecology of the Giant Octopus are needed to resolve questions about its fishery potential, population regulation, ecology and evolution.
Our work on this species has been greatly enhanced by the participation of the Alaskan natives and fishermen who live in Prince William Sound and who regularly harvest octopus for their own use. In particular, the participation of Jerry Totemoff (Tatitlek), Mike Eleshansky (Chenega Bay), and Simeon Kvashnikoff (Port Graham) has been invaluable in teaching us about octopus habits and habitats; thereby helping us to focus our research.
Also see the Alaska Native Knowledge Network and The American Indian Heritage Foundation.
A bibliography of references related to the Giant Octopus Enteroctopus dofleini.
